Late stage call setup management

ABSTRACT

A method for revenue assurance in a telephone network. The method comprises receiving a call request from a first user device on a network to a second user device, where the user device associated with a first user account has an account credit value insufficient to complete the requested call. A call timer duration is set to instantly expire on encountering a chargeable event. The call is continued toward the second user device. Upon encountering a chargeable event, the call is released. The chargeable event may be presenting a Ring Back Tone to the caller and confirming that the second device is ringing. The chargeable event may be detecting when the call has been answered.

FIELD OF INVENTION

In the field The subject matter relates to method and systems for latestage telephony revenue assurance and billing verification for callerswith insufficient credit.

BACKGROUND

Many users at the mobile prepaid market extremity use prepaid as a“pretext to calling”, ringing and hanging up before the called partyanswers in order to deposit a “missed call” and thereby freely signalingthe other party to call back. In a calling party pays world, “misscalling” in the manner and the resultant return, effectively reversesthe connection and the billing between the caller (A) and the calledparty (B) as incoming calls are connected without cost to the recipient.

When a prepaid subscriber requests a call, the servicing operatorbilling system verifies that the caller has sufficient credit tocomplete the call before permitting the call to continue and progressbeyond setup to the terminating phase (ringing and answering).

This early, originating, call setup stage billing verification ensuresthat the caller at minimum has sufficient credit to cover the firstbilling increment if the call is permitted to progress to the dialeddestination and the call is answered. It is a revenue assurance policythat only permits calls go to completion if the user has the necessaryfunds in order to pay for the resultant voice communication.

The quantum of prepaid credit required to progress the call to aterminating phase may be dependent on whether the caller is on a persecond or per minute billing protocol. However the credit requiredtypically covers the first minute of use since the terminating carrieroften bills the originating carrier on a per minute basis to terminatetraffic on its network.

Prepaid telephony is premised on cyclical top up, and the need forairtime replenishment is well known in the art, since a prepaid balancedepletes with use over time. Many users however regularly findthemselves without sufficient prepaid credit remaining in their accountto raise a call. These users become dormant as they can no longer accessthe network and engage the ring to drive their own inbound connectionsusing the “miss calling protocol”.

There is thus a need to continue servicing these users without credit,along the established call path, in a signaling context, permitting themto continue “miss calling”, without disrupting the core prepaid premisegoverning telephony, which is “users are required to have sufficientprepaid credit (airtime) in order to engage in a voice conversation”.

BRIEF SUMMARY OF EMBODIMENTS OF THE INVENTION

A method for revenue assurance in a telephone network comprisesreceiving a call request from a first user device on a network to asecond user device. The user device associated with a first user accounthas an account credit value insufficient to complete the requested call.A call timer duration is set to instantly expire on encountering achargeable event. The call is progressed toward the second user device.A chargeable event is encountered and then the call is released.

In a variant of the method for revenue assurance in a telephone network,the chargeable event is selected from the group comprising a) presentinga Ring Back Tone to the caller and confirming that the second device isringing; and b) detecting when the call has been answered.

In another variant of the method for revenue assurance in a telephonenetwork, the method comprises playing the Ring Back Tone to the firstuser prior to releasing the call.

In a further variant of the method for revenue assurance in a telephonenetwork, the method comprises playing the Ring Back Tone to the firstuser prior to activation and expiration of the call duration timer.

In still another variant of the method for revenue assurance in atelephone network, receiving a call request from a first user device ona network comprises receiving a call request at a mobile switchingcenter (MSC). The method further comprises initiating a network dialogbetween the MSC and a service control point (SCP) whereby the SCPinstructs the MSC to set a call duration timer to instantly expire uponencountering a chargeable event and instructs the MSC to continueprogressing the call toward the second device. On the MSC receivingconfirmation that the second device is ringing, the MSC notifies the SCPthat the second device is ringing. Responsive to being notified that thedestination is ringing, the SCP releases the call.

In another variant of the method for revenue assurance in a telephonenetwork, the call timer duration is set to one or zero seconds.

In a further variant, a telephone network comprises: a first user deviceconfigured to request a call; a mobile switching center (MSC); a servicecontrol point (SCP); a prepaid billing manager; and a second user deviceconfigured to receive a call from the first user device. The telephonenetwork is configured to receive a call request from the first userdevice to the second user device, wherein the first user device isassociated with a first user account that has an account credit valueinsufficient to complete the requested call. The prepaid service controlpoint is configured to check the account value of the first user accountand verify the account value is insufficient to place a call. The SCP isconfigured to instruct the MSC to set a call duration timer to instantlyexpire upon the MSC encountering a chargeable event. The MSC isconfigured to notify the SCP that the chargeable event was encountered.The MSC is configured to release the call upon encountering thechargeable event.

Other features and aspects of the invention will become apparent fromthe following detailed description, taken in conjunction with theaccompanying drawings, which illustrate, by way of example, the featuresin accordance with embodiments of the invention. The summary is notintended to limit the scope of the invention, which is defined solely bythe claims attached hereto.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A. is a conceptual timeline depicting key events in a telephonycall and highlighting early versus late stage call release oninsufficient credit.

FIG. 1B. is a series of call flow charts that similarly depict thedistinction between early versus late stage call release on insufficientcredit.

FIG. 2. is a call process step ladder illustrating late stage billingassurance and verification in a preferred INAP embodiment.

FIG. 3. is a call process step ladder illustrating late stage billingassurance and verification in an alternate INAP embodiment.

Skilled artisans will appreciate that elements in the drawings areillustrated for simplicity and clarity and have not necessarily beendrawn to scale. For example, the dimensions of some of the elements inthe figures may be exaggerated, relative to other elements, and somesteps condensed and others omitted to improve understanding of theembodiments of the present invention.

Further it will be appreciated that elements presented as “italicizedtags” are simply commentary highlighting key events. While these tagsare placed within the step ladder sequence, between lines connectingnetwork node elements (A MSC SCP BAL B), they are not intended tologically connect these network nodes nor are they originating from thesaid nodes. Tags include: announcements (such as “Insufficient Airtime”and “1× missed call”) and logic (such as setting “0/1 Second DurationTimer” and expiring the same).

GLOSSARY OF TERMS

-   CAMEL: Customized Application for Mobile network Enhanced Logic-   INAP: Intelligent Network Application Protocol-   ISUP: ISDN User Part-   ISUP ACM: Address Complete Message-   ISUP ANS: Answer-   ISUP IAM: Initial Address Message-   ISUP REL: Release-   IVR: Interactive Voice Response-   MAP: Mobile Application Part-   MSC: Mobile Switching Center-   RBT: Ring Back Tone-   SCP: Service Control Point-   SIP: Session Initiation Protocol-   SMS: Short Message Service-   SS7: Signaling System Seven-   USSD: Unstructured Supplementary Services Data-   VOIP: Voice over Internet Protocol-   3GPP: Third Generation Partnership Program

DETAILED DESCRIPTION

Telephony calls are logically and physically completed in two phases:

-   1. An Originating Phase which describes the connection between the    caller and the servicing Switch.-   2. A Terminating Phase which describes the connection between the    servicing Switch and the called party.    These two distinct phases permit intelligent call handling and    control logic to execute between the originating and the terminating    processes. Thus a call between “A and B” actually consists of two    independent call paths (“legs”) bridged together. As such, a    servicing switch can conduct dialogs and call control with the    caller and the called party, separately and independently.

The embodiments describe advanced billing procedures for telephony callsand by illustration, references call flows in Mobile Telephony Networksutilizing ISUP/SS7 and INAP circuit switching. However, suitably skillednetwork switching and billing artisans will appreciate the principlestaught herein are readily applied to different network architectures andsignaling protocols.

These include different network switching and signaling topologies andprotocols, different billing control and sequencing, including withoutlimitation, networks that utilize CAMEL, and networks that employ VOIPPacket Switching and Signaling protocols such as SIP. Further, networkreal time billing systems, may utilize “recurring quota allocations” intheir revenue assurance process, which in particular may include billingtransactions between network nodes that follow call release, and whichare therefore not relevant to this disclosure.

This present invention and the methods disclosed herein, shifts thebilling verification governing operator revenue assurance from the early“Originating” call setup phase, to the late “Terminating” phase whichincludes ringing, ringback and answering events, thereby permittingaccess to the ring for users who have depleted their prepaid credit orwho have no credit.

Describing this “early versus” stage billing assurance and verificationfor users with insufficient credit, with reference to FIG. 1A:

A100: User A dials telephone number of user B.

A101: The call setup request is received by the servicing (originating)MSC. The MSC establishes a MAP dialog (not shown) with the Prepaid SCPwhich verifies the credit sufficiency of caller A to complete therequested call to B.

The SCP on determining that caller A has insufficient credit to completethe call, instructs the MSC to announce to the caller that they haveinsufficient credit and to releases the call.

A102: The user is disconnected.

At this point the call has thus been released at the early, originatingsetup phase. This sequence describes the current state of the prepaidbilling art for callers with insufficient credit.

Describing now the presently disclosed advance to the prepaid art wherethe call is permitted to progress beyond the early originating callsetup phase and again with reference to FIG. 1:

A101: On determining the user has insufficient credit to complete thecall, the SCP, instead of instructing the MSC to announce the to thecaller they have insufficient credit and then releasing (disconnecting)the call, the SCP now instructs the MSC to continue processing the calland to set the call timer duration (the initial quota duration) toinstantly expire on encountering a chargeable event.

The MSC progresses the call toward the dialed destination, for exampleby transmitting an ISUP IAM (Initial Address Message).

A103: The MSC on receiving confirmation that the destination is ringing,for example by receiving an ISUP ACM, the network plays a RBT (Ring BackTone) to caller A. RBT presentation precipitates a chargeable eventwhich in turn activates the call duration timer which governs themaximum allowable time for a call on encountering a chargeable event.The call duration timer is set to expire instantly on activation whichresults in the MSC releasing the call. Releasing the call after RBTpresentation results in a “missed call” displayed on the B party device.This sequence discloses Late Stage One (L1 ) revenue assurance.

A104: In an alternate embodiment where RBT is not defined as achargeable event and in cases where calls are immediately answered, theMSC permits the destination to continue ringing until the call is eitheranswered (ISUP ANS) or until a maximum ring timer expires. On detectingthat the B party has answered the call, the initial call duration quotaand the timer that monitors the call duration instantly “fires andexpires”.

That is, once the MSC encounters the “answer” chargeable event, the callduration timer “fires” (begins count down). And since the call durationtimer for a caller with insufficient credit is set to a maximum of justone second, as detailed below, it immediately “expires” (reaches zero).On call duration expiry the network announces to caller A that their“Airtime is exhausted” and releases the call. This call sequencediscloses Late Stage Two (L2) revenue assurance.

It will be appreciated that the “Airtime exhausted” notification tocaller A, in the exemplary embodiment, is a voice announcement on theexisting call. However alternate notifications, for example playingspecific tones to caller A, or sending the caller a network generatedmessage after releasing the call, may achieve the same result. Similarlycall event counters may “count up” to a maximum allowable time ratherthan “count down” to zero.

Furthermore in addition to the announcement, or in place of theannouncement, network service options may be presented to caller A onthe existing call setup utilizing IVR (interactive voice response) menusor via alternate bearers and protocols including without limitation, viaSMS message, via USSD messaging or via Internet Protocol data messagingor “in app” (in application) notifications and options, permitting theuser to replenish credit or to select alternate options to notify thecalled party. Notwithstanding the announcement and options presented toA, the call leg to B is released.

Prepaid Billing methods are well understood. In particular prepaidcredit verification during the Originating BCSM (Basic Call StateModel). BCSM is a fundamental concept for intelligent networking controlwhere the call goes through a number of predefined states. These statesof the call are described in the BCSM and generally follow the ISUPsignaling path.

Billing standards published by 3GPP (Third Generation PartnershipProgram) and INAP (Intelligent Network Application Protocol) identifyseveral distinct chargeable events in an originating voice call. Thesechargeable events include:

-   1. Call Setup Voice channel seizure-   2. Caller Ring Back Tone presentation-   3. Called party answers    These events correspond to well known PICS (points in call) that    describe the originating BCSM and the intelligent network triggers    and event detection points that may be armed to notify a SCP    (Service Control Point). These events may also be programmatically    subscribed to, by an SCP during a call setup dialog with the MSC,    utilizing the well understood RRBSCM (Request Report BCSM) and    similar Intelligent Networking protocols.

Periodic billing verification during a call connected phase is also wellunderstood. Intelligent Networks support an internal network dialogbetween the originating MSC and the Prepaid SCP and Billing System thatpermits the billing system to audit and control call progression andduration, which is dependent on the amount of credit remaining in thecallers account. The prior art MSC/SCP dialog that governs realtime orsubstantially realtime billing is well known.

In a preferred embodiment the SCP selectively requests the MSC to enableRBT presentation as a “chargeable event”, only for callers withinsufficient credit. The desired effect of selectively enabling thischargeable event in this manner, is that callers who have sufficientcredit are not charged for RBT while calls from users with insufficientcredit trigger the “zero or one second” initial quota call durationtimer method as described, on RBT presentation. On encountering the RBTevent the MSC timer “fires and expires” substantially simultaneouslywithout actually charging the caller since the call is instantlyreleased. On this call duration timer expiration, the network announcesto caller A that their “Airtime is exhausted” and releases the call.This call sequence discloses Late Stage One (L1 ) revenue assurance.

In an alternate embodiment, the network uniformly enables RBTpresentation as a “chargeable event” for all callers, while stillpermitting calls from users with insufficient credit to engage the ringwithout payment, since these callers without credit would then triggerthe “zero or one second” initial quota call duration timer method, asdescribed above, on RBT presentation.

Since “miss calling” is predicated on the caller hearing the RBT anddisconnecting the call before it is answered, it consumes valuablenetwork resources without generating revenue. Many networks experiencehigh volumes of intentional “miss calling” (typically 20% of all callsare missed calls, where the caller disconnects before answer, and insome emerging market regions miss calling is an astronomical 70%).Enabling RBT as a chargeable event recovers network costs and attenuatesuse and abuse.

Since many subscribers are billed on a “per second basis”, legitimatecallers who are intent on actually completing the connection andconducting a voice conversation would, on RBT being a chargeable event,only incur a marginal increase in communication cost, in setting up thecall and “ringing the destination”, compared to the actual cost of theconnected and completed conversation which is typically of longerduration than ringing.

The net and desired result, is these “less cost sensitive and moreeconomically empowered users” then subsidize “the penny conscious poor”who cannot afford to pay for a call, as well subsidizing those who haveexhausted their airtime and can no longer ring to signal and requestcall back in the state of the prior call completion art. Since the Bparty is already paying to connect the A party by calling them back onreceiving a “missed call”, paying a little extra to subsidize and enable“miss calling” as disclosed in this present invention, is sociallyacceptable.

An additional positive effect enabling RBT as a chargeable event, isthat callers will only ring for long duration when they urgently need totalk. Since many users today have their phone in close proximity, andalmost all users “screen calls on caller identity”, they are instantlyalerted by the ring and acutely aware of an incoming call. If theychoose not to answer the call within the first few moments of ringing,they are “subtly and silently” signaling to the caller that they are notavailable to speak or do not wish to speak at this time.

Since with RBT as a chargeable event the caller is now incurring cost toring, they are enticed to disconnect sooner if their calls continue toring without being answered early on. This reinforces a social protocolthat the more important the call, the longer the caller will ring.However it now does so at some cost to the caller. The result, in themain, is shorter duration ringing which in itself delivers a valuablelifestyle enhancing benefit in that it does not disturb the called partyas much as incessant longer ringing currently does. While rings lackcontext, ring frequency and duration transmits intent.

In yet a further embodiment L1 Late Stage Revenue Assurance operates bythe SCP requesting the “Alerting” event notification in order toinstruct the MSC to release the call on RBT presentation to caller A,before the call is answered by the called party B. In relatedembodiment, absent the ability of the SCP to selectively enable RBT as achargeable event, the SCP requests notification from the MSC on B party“Alerting” (ringing). On receiving notification that the B party isringing, the SCP momentarily delays instructing the MSC to release thecall in order to permit time for the RBT to present to caller A. Such anintentional delay on instructing would amount to one or two seconds,sufficient to provide adequate time for RBT presentation to the caller.

Describing Early Stage Release (Prior Art) with reference to FIG. 1B:

B100: User A dials user B requesting a telephony call.

B101: The network performs a credit verification to determine whetherthe caller has sufficient credit to complete the call.

B102: If caller does not have sufficient credit, the network informscaller that there is “insufficient credit to complete the call”.

B103: The network releases the call and terminates the request.

Describing Late Stage Release (L1 Newly Disclosed) with reference toFIG. 1B:

B110: User A dials user B requesting a telephony call.

B111: The network performs a credit verification to determine whetherthe caller has sufficient credit to complete the call.

B112: If caller A does not have sufficient credit, the network sets aninitial call duration timer equal to “zero or one” seconds and permitsthe call to continue.

B113: The network progresses the call towards the B party and monitorsamongst other conditions, for “ringing” and “answered” events.

B114: If the B party rings, the network presents a Ring Back Tone (RBT)to caller A.

B115: After presenting RBT the network releases the call and terminatesthe request.

Describing Late Stage Release (L2 Newly Disclosed) with reference toFIG. 1B:

B120: User A dials user B requesting a telephony call.

B121: The network performs a credit verification to determine whetherthe caller has sufficient credit to complete the call.

B122: If caller A does not have sufficient credit, the network sets aninitial call duration timer equal to “zero or one” seconds and permitsthe call to continue.

B123: The network progresses the call towards the B party and monitorsamongst other conditions, for “ringing” and “answered” events. If the Bparty rings, the network presents a Ring Back Tone (RBT) to caller A(not shown). On hearing RBT the caller may choose to disconnect thecall.

B124: If the B party answers, or the call is diverted, for example to avoicemail service which in turn answers the call, the initial callduration timer activates and instantly expires. The network informscaller A that their “airtime is exhausted”.

B125: The network releases the call and terminates the request.

Describing the preferred L1 Late Stage Revenue Assurance embodiment ingreater detail with reference to FIG. 2:

200: User A requests a new call by dialing telephone number of user B.

201: The MSC sends an InitialDP (Initial Detection Point) eventnotifying the Intelligent Network SCP of the new call.

The SCP in turn processes the InitialDP request and sends an “initialquota request” to the Prepaid Balance Manager (BAL). After authorizingthe user, BAL grants the available maximum duration quota for the callto the SCP. The duration quota describes the maximum initial callduration that the MSC then administers using well known call controltimers.

In the preferred embodiment BAL calculates the duration Quota (Q) bydividing the available prepaid Credit (C) by the applicable call Tariff(T):Q=C/TSince the subject matter of this present disclosure is related tocallers who have insufficient credit to complete the call, C isnecessarily less than T. For illustrative purposes assuming:

-   T 32 “2 cents per second” and-   C=“1 cent” then-   Q=“½ (one half) seconds”    Since calls are typically monitored and clocked in one second    increments, duration Q may be rounded up or down to the nearest    second. In the case of insufficient credit balance, as illustrated    above, duration Q thus computes to either “zero” or “one” second in    the exemplary embodiment. If a prepaid balance is negative, Q may be    reset to “zero” or “one”.

The intended consequence in permitting the call to progress beyond theearly originating phase on insufficient credit, together with an initialduration quota of just “one or zero seconds”, is to instantly force callrelease the moment a chargeable event is encountered, thereby permittingthe caller to “signal” B, to ring the called party, without permittingthe call to fully progress to “conversation” (speech) since the maximumallowable connected call duration is exhausted on encountering achargeable event (for example on RBT or answering).

202: ApplyCharging

The SCP sends “ApplyCharging” to the MSC. This sets up the maximum callduration timer (quota) as described above, which is then managed by theMSC.

203: RRBCSM

The SCP sends “Request Report BSCM” to the MSC. This requests the MSC tonotify the SCP on events, including without limitation, RINGING, ANSWERand DISCONNECT so the SCP may take any appropriate action.

204:CONTINUE

The SCP sends “Continue” to the MSC. This directs the MSC to continuecall processing into the terminating phase, towards the B party.

205: A is logically connected to B.

206: On receiving confirmation that the B party is “ringing” the MSCsubstantially simultaneously presents RBT (Ring Back Tone) to caller A,and optionally sends an event report (ER BCSM not shown) notifying theSCP.

207. On presenting RBT to the caller, this chargeable event activatesthe initial call quota duration timer set in the MSC, which instantly“fires and expires”. The MSC releases the call to complete L1 Late StageRevenue Assurance by not permitting the call to progress beyond theringing and RBT state. The MSC may optionally announce to the caller,that their “Airtime has been exhausted” before releasing the call, toencourage users to replenish their credit (not shown).

In L2 Late Stage Revenue Assurance described following, the MSCinstantly releases the call on “Answer” since the initial durationquota, which is set to “0 or 1 second” by the Prepaid Balance Manager asdescribed above, expires immediately once the call is answered. In L1the SCP typically also requests reporting on the “Answer” event in orderto safeguard against inadvertent billing leakage, by explicitlyreleasing the call in the event that the MSC fails to expire the timerand release the call.

Describing the L2 Late Stage Revenue Assurance model in greater detailwith reference now to FIG. 3:

300: User A requests a new call by dialing telephone number of user B.

301: The MSC sends an InitialDP (Initial Detection Point) eventnotifying the Intelligent Network SCP of the new call.

The SCP in turn processes the InitialDP request and sends an “initialquota request” to the Prepaid Balance Manager (BAL). After verifying thecredit balance available to the user, BAL grants the available durationquota for the call to the SCP. The duration quota describes the maximuminitial call duration that the MSC then administers using well knowncall timers.

The Initial Quota Duration is computed as described above.

Again the intended consequence in permitting a call with insufficientcredit to progress beyond early stage setup, together with an initialduration quota of just “one or zero seconds”, is to instantly force callrelease the moment the chargeable event is encountered, thus permittingthe caller to “signal”, to ring the called party, without permitting thecall to fully progress to “conversation” (speech).

302: ApplyCharging

The SCP sends “ApplyCharging” to the MSC. This sets up the initial quotacall duration timer managed by the MSC.

303: RRBCSM

The SCP sends “Request Report BSCM” to the MSC. This requests the MSC,for example, to inform the SCP on, amongst other events, RINGING, ANSWERand DISCONNECT.

304:CONTINUE

The SCP sends “Continue” to the MSC. This directs the MSC to continueprocessing and progressing the call towards B.

305: A is logically connected to B.

On receiving confirmation that the B party is “ringing” the MSCsubstantially simultaneously presents RBT (Ring Back Tone) to caller A.

306: On receiving RBT, caller A may choose to end the call since theyhave successfully signaled the B party.

307: The B party answers the call.

308: The MSC sends an event report (ER BCSM ANSWER) to the SCP.

309: The MSC initial call duration timer activates on encountering theanswer chargeable event and instantly expires.

In one embodiment utilizing a single quota system the MSC announces“Airtime Exhausted” to caller A and releases the call.

In an alternate embodiment utilizing a “recurring quota” system, when aninitial quota timer is about to deplete, the MSC would send an eventreport to the SCP requesting a further interim quota. Since the subjectmatter of the present invention relates to callers who have insufficientcredit, the SCP would in this instance not send additional ApplyChargingrequests to the MSC since the user has exhausted their airtime quote.The SCP would therefore simply instruct the MSC to release the call.

Notwithstanding such a “recurring quota system”, this present inventionsets the initial quota timer to an absolute minimum for callers withinsufficient credit, to ensure the call duration limit is reached themoment a chargeable event is encountered. Since the timer essentiallyexpires immediately on activation, there is practically no opportunityfor the MSC to request a further interim quota and consequently the callis released, typically after announcing that airtime credit has beenexhausted.

310: The MSC instantly releases the call to complete L2 Late StageRevenue Assurance by not permitting the call to continue with speech.

In a further embodiment Late Stage Billing Assurance and creditverification may selectively be applied, dependent on the called partydestination. For example, the SCP and BAL nodes may only continue callsbeyond early stage with an instantly expiring duration timer, if thecall is set to terminate on the home network or if the call is adomestic rather than an international call.

The ability to selectively apply the Late Stage Release methodsdisclosed, may limit any carrier exposure, since “off net” calls thatare permitted to progress beyond call setup may incur signaling and orterminating fees, particularly if the call is answered on a foreignnetwork.

The above methods disclosed permit prepaid users with insufficientcredit to complete a call request, and users with zero prepaid credit,to engage the ring and signal the dialed party using the well known“missed calling” protocol while simultaneously adhering to revenueassurance practices that prevent such users from fully progressing thecall request to speech without paying.

While various embodiments of the present invention have been describedabove, it should be understood that they have been presented by way ofexample only, and not of limitation. Likewise, the various diagrams maydepict an example architectural or other configuration for theinvention, which is done to aid in understanding the features andfunctionality that can be included in the invention. The invention isnot restricted to the illustrated example architectures orconfigurations, but the desired features can be implemented using avariety of alternative architectures and configurations. Indeed, it willbe apparent to one of skill in the art how alternative functional,logical or physical partitioning and configurations can be implementedto implement the desired features of the present invention. Also, amultitude of different constituent module names other than thosedepicted herein can be applied to the various partitions. Additionally,with regard to flow diagrams, operational descriptions and methodclaims, the order in which the steps are presented herein shall notmandate that various embodiments be implemented to perform the recitedfunctionality in the same order unless the context dictates otherwise.

Although the invention is described above in terms of various exemplaryembodiments and implementations, it should be understood that thevarious features, aspects and functionality described in one or more ofthe individual embodiments are not limited in their applicability to theparticular embodiment with which they are described, but instead can beapplied, alone or in various combinations, to one or more of the otherembodiments of the invention, whether or not such embodiments aredescribed and whether or not such features are presented as being a partof a described embodiment. Thus the breadth and scope of the presentinvention should not be limited by any of the above-described exemplaryembodiments.

Terms and phrases used in this document, and variations thereof, unlessotherwise expressly stated, should be construed as open ended as opposedto limiting. As examples of the foregoing: the term “including” shouldbe read as meaning “including, without limitation” or the like; the term“example” is used to provide exemplary instances of the item indiscussion, not an exhaustive or limiting list thereof; the terms “a” or“an” should be read as meaning “at least one,” “one or more” or thelike; and adjectives such as “conventional,” “traditional,” “normal,”“standard,” “known” and terms of similar meaning should not be construedas limiting the item described to a given time period or to an itemavailable as of a given time, but instead should be read to encompassconventional, traditional, normal, or standard technologies that may beavailable or known now or at any time in the future. Likewise, wherethis document refers to technologies that would be apparent or known toone of ordinary skill in the art, such technologies encompass thoseapparent or known to the skilled artisan now or at any time in thefuture.

A group of items linked with the conjunction “and” should not be read asrequiring that each and every one of those items be present in thegrouping, but rather should be read as “and/or” unless expressly statedotherwise. Similarly, a group of items linked with the conjunction “or”should not be read as requiring mutual exclusivity among that group, butrather should also be read as “and/or” unless expressly statedotherwise. Furthermore, although items, elements or components of theinvention may be described or claimed in the singular, the plural iscontemplated to be within the scope thereof unless limitation to thesingular is explicitly stated.

The presence of broadening words and phrases such as “one or more,” “atleast,” “but not limited to” or other like phrases in some instancesshall not be read to mean that the narrower case is intended or requiredin instances where such broadening phrases may be absent. The use of theterm “module” does not imply that the components or functionalitydescribed or claimed as part of the module are all configured in acommon package. Indeed, any or all of the various components of amodule, whether control logic or other components, can be combined in asingle package or separately maintained and can further be distributedacross multiple locations.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination or as suitable in any other describedembodiment of the invention. Certain features described in the contextof various embodiments are not to be considered essential features ofthose embodiments, unless the embodiment is inoperative without thoseelements.

Additionally, the various embodiments set forth herein are described interms of exemplary block diagrams, flow charts and other illustrations.As will become apparent to one of ordinary skill in the art afterreading this document, the illustrated embodiments and their variousalternatives can be implemented without confinement to the illustratedexamples. For example, block diagrams and their accompanying descriptionshould not be construed as mandating a particular architecture orconfiguration.

What is claimed is:
 1. A method, comprising: receiving, by a mobileswitching center (MSC) of a telephone network, during an originatingcall setup phase of a call, a telephony call setup request from a firstuser device; wherein the telephony call setup request identifies atelephone number associated with a second user device; wherein the firstuser device is associated with a user account having a credit value thatis insufficient to complete a terminating setup phase of the call;initiating, by the MSC of the telephone network, a network dialogbetween the MSC and a service control point (SCP) whereby the SCPinstructs the MSC to set the maximum call duration timer to the valuethat is less than or equal to 1 second and instructing the MSC tocontinue the call through the terminating setup phase toward the seconduser device; continuing, by the MSC of the telephone network, after thesetting of the maximum call duration timer, to progress the call throughthe terminating setup phase toward the second user device; receiving, bythe MSC, a confirmation that the second user device is ringing; andreleasing, by the MSC, the call based on the confirmation that thesecond user device is ringing.
 2. The method of claim 1, furthercomprising: activating, by the MSC of the telephone network, the maximumcall duration timer upon encountering a chargeable event during theterminating setup phase of the call; and releasing, by the MSC of thetelephone network, the telephony call after the maximum call durationtimer expires.
 3. The method of claim 2, wherein the chargeable eventincludes: an event of presenting a Ring Back Tone to the first userdevice, and an event of answering the call at the second user device. 4.The method of claim 1, further comprising: presenting, by the MSC of thetelephone network, a Ring Back Tone to the first user device onconfirming that the second user device is ringing.
 5. The method ofclaim 1, further comprising: releasing, by the MSC of the telephonenetwork, the telephony call after confirming that the second user deviceis ringing.
 6. A telephone network, comprising: a first user deviceconfigured to request a call; a mobile switching center (MSC); a servicecontrol point (SCP); a prepaid billing manager; a second user deviceconfigured to receive the call from the first user device; wherein: thetelephone network is configured to receive, at the MSC, a telephony callsetup request from the first user device during an originating callsetup phase of the call; the first user device is associated with a useraccount having a credit value that is insufficient to complete aterminating setup phase of the call; the SCP is configured to determinethat the user account has the insufficient account credit value tocomplete the terminating setup phase of the call; the SCP is configuredto instruct, based on the insufficient account credit value, the MSC toset a maximum call duration timer to a value that is less than or equalto 1 second; the MSC is configured to notify the SCP that the maximumcall duration timer has expired; and the MSC is configured to releasethe call upon being notified that the maximum call duration timer hasexpired.
 7. The network of claim 6, wherein the MSC is furtherconfigured to: activate the maximum call duration timer uponencountering a chargeable event during the terminating setup phase ofthe call; and release the telephony call after the maximum call durationtimer expires.
 8. The network of claim 7, wherein the MSC is configuredto present a Ring Back Tone to the first user device on confirming thatthe second user device is ringing.
 9. The network of claim 8, whereinthe chargeable event includes: an event of presenting a Ring Back Toneto the first user device, and an event of answering the call at thesecond user device.
 10. The network of claim 7, wherein the MSC isfurther configured to release the telephony call after confirming thatthe second user device is ringing.
 11. A method, comprising: receiving,by a network switching center of a telephone network, during anoriginating call setup phase of a call, a telephony call setup requestfrom a first user device; wherein the telephony call setup requestidentifies a telephone number associated with a second user device;requesting, by the network switching center, a call processinginstruction from a service control point; requesting, by the servicecontrol point, a maximum call duration quota from a billing system;determining, by the billing system, that an account associated with thefirst user device has insufficient credit value to complete aterminating setup phase of the call; returning, by the billing system,the maximum call duration quota to the service control point; whereinthe maximum call duration quota is set to a value that is less than orequal to 1 second; instructing, by the service control point, based onthe maximum call duration quota, the switching center to continue to thecall through the terminating setup phase; and configuring the telephonenetwork to disconnect the call during the terminating setup phase whenthe maximum call duration quota has been reached.
 12. The method ofclaim 11, wherein the terminating setup phase of the call comprises aringing state.
 13. The method claim 11, further comprising: responsiveto the second user device ringing, presenting, by the service controlpoint, a Ring Back Tone to the first user device.
 14. The method ofclaim 13, further comprising: responsive to the Ring Back Tone beingpresented to the first user device: indicating, by the service controlpoint, that the maximum call duration quota has been reached andreleasing, by the service control point, the call.